.tbg is Infinity Engine game file
Key Features: .TBG File Extension
What is an .TBG file?
The tbg file extension is associated with the Infinity a video game engine developed by BioWare and used by various computer games, like Baldur's Gate etc.
The tbg file stores some kind of data used by this game engine.
The TBG files were found in open-source variant of Infinity Engine called GemRB.